WASHINGTON -- The United States is keeping all options open in dealing with North Korea's nuclear ambitions, Defense Secretary Donald Rumsfeld said Sunday when asked if Washington had ruled out using military force against Pyongyang.

"All options are still on the table with North Korea," Rumsfeld said, though he repeated President George W.

Bush's insistence that Washington has no plans to invade the North, AFP reported.

"But does that mean the United States or South Korea would, would take an attack from North Korea and not respond? Of course not," Rumsfeld said on the "Fox News Sunday" program.

Bush last week held out the prospect of political and economic help for North Korea if it verifiably dismantled programs based on enriched uranium and plutonium.

Meanwhile, North Korea rejected an ongoing wave of international diplomatic efforts aimed at ending its nuclear weapons program, saying it would negotiate only with the United States.

White House National Security Adviser Condoleezza Rice, speaking on NBC, said Washington would continue to work with regional allies such as China, Japan and South Korea to solve the crisis.

"North Korea may escalate and may continue to escalate but they are doing so at the cost of their own isolation," Rice said.

Earlier, Pyongyang said it would not allow the United States to "internationalize" the dispute, and specifically said the United Nations should not be involved in trying to resolve the crisis.

The comments by first Vice Foreign Minister Kang Sok-ju came just one day before the UN Security Council was due to discuss the issue in New York and a day after UN Secretary General Kofi Annan's special envoy, Maurice Strong, ended a four-day visit to Pyongyang.

"The DPRK (North Korea) and the U.S. should sit face-to-face to solve the nuclear issue on the Korean Peninsula," the state-run Korean Central News Agency quoted Kang as saying. In Washington, Chinese Ambassador Yang Jiechi said his country was committed to a peaceful solution of the crisis and said "We hope the United States and DPRK will hold talks soon."